Some cleanup for issues with legacylogger

Primarily, this adds a check to make sure the class exists before trying to use it. It should be there, since it has been addMap'ed to the loader, but obviously it isn't.

Also re-evaluated where the Xoops\Core\Logger is instantiated, moving it ahead in the process a little bit.
Converting preload to events

Preloads are an event handling system, but limited by both a misleading name, and the inability to dynamically register a new event listener. This change takes care of both issues. Full backward compatibility is mantained for now.

Xoops\Core\Events takes over for XoopsPreload
Xoops\Core\PreloadItem takes over for XoopsPreloadItem
Xoops::getInstance()->events() takes over for ->preload()

modules/(name)/preloads/*.php processing is unchaged (that is the 'preload' part.)
New  method addListener('event.name',callable) to register listeners on the fly
Fix monolog/preloads/core.php error - undefined var $configs
Remove errant vendor directory
Fix monolog default log path, PSR2 cleanups in new loggers
Remove class loader reference used during development
Merge pull request #23 from geekwright/master

New Events class, Cleanup for legacylogger, monolog